prout outdrive

[mikemacdonald]

we have a Prout Snowgoose with a Silettesonic outdrive and a Yanmar 3ym30.The flexible coupling between the gearbox and leg is supplied by Sillette and is huge. Is it absolutely necessary to have a flexible coupling, if I can do away with it I can move the engine aft by about 6" and give better access to the front, or is there another solution?

 

[davidbains]

I would have thought that the large flexible coupling is necessary, probably due
to the leverage on the long leg. Presumably you are finding it awkward to get at
the belts and water pump. 6'' isn't much of a gain. I'd be inclined to leave things
as they are.

 

[mikemacdonald]

Hmm, hadn't thought about the leverage, thankyou

 

[boatmike]

It is absolutely essential to leave it there. If you don't the movement of the engine will quickly knacker the bearings in the back of the gearbox and the front of the leg. Don't even think about it!

 

[Birdseye]

Apart from anything else you need a flexible coupling to isolate the engine vibes from the hull since the silette leg is directly bolted to the transom. however, there will be other makers of flexible couplings that might substitute and be shorter - I used an R&D one once, if they are still in business.

Normally Snowgooses have a drilled hole in the front engine bulkhead to allow for alternator bolt removal. No doubt other holes for other purposes. this space problem was what put me off the 3GM when I re-engined my old Quest

 

[brianrunyard]

Don't know your particular installation but another reason for the flexible coupling is the fact that the engine will be on flexible mounts, without the flexible coupling you'd wreck the transom.

 

[Superstrath]

Hmm, mine's got a 3HM30 and I can do anything at the front of the engine, alternator, pump etc. There is a bit of soundproofing that can come out to give more room.

Alistair

 

[mikemacdonald]

We have a 10" diameter hole in the lower bulkhead with a manhole type cover that gives access to the waterpump,just. I think I'm going to leave as is, and will drill some20mm holes opposite the necessary bolts to adjust the alternator and waterpump fixings. Thanks for everyones input, much appreciated. /forums/images/graemlins/cool.gif